DOWNTOWN SAN DIEGO  Minutes after it was announced he would leave office, Mayor Bob Filner apologized for the upheaval that has gripped San Diego but insisted that his downfall stems from a “lynch mob” mentality.

In alternately contrite and defiant remarks, he acknowledged his behavior led to the climate that forced him to resign but denied he sexually harassed anyone.

“The city should not have been put through this, and my own personal failures were responsible,” he said in the packed City Council chambers Friday.

He apologized to the women he offended but also his supporters who cheered him during his nearly 15-minute speech at City Hall

“I think I let you down,” he said. “We had a chance to do a progressive vision in this city for the first time in 50 years.”

Filner touched on his record as a 1960s civil rights Freedom Rider, his two decades in Congress and suggested his brief tenure as mayor is over because of a conspiracy.

“Not one allegation … has even been independently verified or proven in court,” he said. “But the hysteria that has been created is the hysteria of a lynch mob.”

He said the media fed the hysteria and challenged news organization to examine what he said they had helped create.

Political opponents found the weapons they needed in his own failures, he said. He provided the ammunition that he said led widespread rumor and innuendo from what he has acknowledged as inappropriate and wrong behavior.

“But there are well-organized interests who have run this city for 50 years who pointed the gun, and the media and their political agents pulled the trigger,” he said.

He ignored one fact that gave the claims against him credibility from the start: Some of the most serious accusations came from people who had been his closest political allies.

His argument he was a victim fell flat with some.

“There were some pieces of it that didn’t show he understood the public’s feelings, but we’ve seen that throughout this episode,” said City Council President Todd Gloria, who becomes the city’s interim mayor at 5 p.m. next Friday. “It was uneven.”

During his contrite moments, Filner said he never meant to offend anyone, especially the nearly 20 women who have publicly accused him of harassment, groping or tawdry remarks.

“I was trying to establish personal relationships, but the combination of awkwardness and hubris I think led to behavior that many found offensive,” he said.

He said he will try to make amends in “any suitable manner” but maintained a mob mentality led to his resignation.

He became emotional when talking about his former fiancée, Bronwyn Ingram, who left him shortly before the scandal erupted that is driving the city’s 35th mayor from office.

“I love you very much,” he said in a halting voice. “You came to love San Diego as much as I did, and you did memorable things in the time you were first lady.”

County Republican Party Chairman Tony Krvaric, among Filner’s harshest longtime critics, said he had some sympathy for Filner at the outset of his speech.

“But then he careened off and went back to saying he had done nothing wrong and this was all a witch hunt. He still doesn’t get it, and that’s sad,” he said.

Filner said he is continuing to get professional help for what he has described as the “monster” inside him.

So it was an interesting choice of words when he accused media organizations and political opponents of creating a climate where he said rumors become allegations, allegations become facts and facts become evidence.

“You have unleashed a monster,” he said.

The city’s soon-to-be former mayor ended his remarks by saying he believes he could have been vindicated.

“Now lord knows I am not perfect — I made a lot of mistakes. But in my heart my desire for a progressive world will drive me to keep going,” he said. “I will not give up.”

Filner then quoted remarks the late Sen. Ted Kennedy made in his concession speech at the 1980 Democratic National Convention.

“The work goes one, the cause endures, the hope still lives, and the dream shall never die,” he said before exiting through a side door.

UC San Diego political science professor Steve Erie said the speech was typified the career of one of the city’s most polarizing politicians ever.

“It’s the two faces of Bob Filner,” he said. “Although there is truth in the lynch mob mentality, he’s partly to blame for that by not offering any defense.”